Question

turns into water. that water causes sea levels to rise.
children play in niugtaq. the land is wet and muddy, so the community built wooden walkways to make it easier to get around the village.
when the sea rises, so do the rivers that flow into it. the bering sea is near the arctic. all the melting ice in the bering sea is causing the ningliq river to rise, too. now the river is eating away at the coastline. the banks of the river are crumbling. over time, the people of niugtaq have watched the water get closer and closer to their front doors. some houses have even fallen into the water.
what is an effect of the rising water in the ningliq river?
people are starting to lock their windows and doors.
riverbanks and nearby homes are falling into the water.
new houses and paths are being built close to the sea.

Explanation:

The text states that the rising Ningliq River is eating away at the coastline, the river banks are crumbling, and some houses have fallen into the water. The first option about locking windows/doors has no relation to rising river water. The third option about building new houses/paths close to the sea contradicts the context as rising water is a problem, not a reason to build near the sea. So the effect of rising water is riverbanks and nearby homes falling into the water.

Answer:

Riverbanks and nearby homes are falling into the water.